Dramatic air quality improvements, with a caveat

Some neighbourhoods in Hamilton have double the cancer death risk from air pollution

On a morning when there was plenty of good news to be celebrated about the improved quality of Hamilton’s air, Jochen Bezner stepped up to the microphone to provide a sobering reality check.

Over the past two decades, there has been a staggering reduction in the amount of air pollution in Hamilton from virtually every source, according to data presented Friday at the Hamilton Air Summit 2018, which was held in the city hall council chambers.

Cancer-causing benzene is down 87 per cent. Benzo-a-pyrene, another carcinogen, is down 76 per cent. Odours from sulphur have been cut by 99 per cent.

Same for nitrogen oxides and sulphur oxides, down by 53 per cent and 47 per cent, respectively. And it’s now five years and counting since Hamilton last experienced a smog advisory.

About 90 per cent of small-diameter particulate matter emissions now come from outside Hamilton’s boundaries, a sign of how much local industry has cleaned up over the past 20 years.

But before everyone hurt their shoulders patting themselves on the back, Bezner drily stated, he pointed out the quality of Hamilton’s air can differ greatly from neighbourhood to neighbourhood.

Bezner, a mechanical engineer, is a resident of the Crown Point neighbourhood in the industrial northeast part of the city, as well as a member of Coalition Against Pollution Hamilton.

He noted some people in his neighbourhood live just a few hundred metres from the coke stacks of steelmakers.

Meanwhile, the closest environment ministry air monitoring station is up to five kilometres to the west, meaning the air quality experienced in his neighbourhood could be significantly worse than the readings being posted.

Bezner noted the ministry’s standard for benzene and benzo-a-pyrene is one additional lifetime cancer case in a million. Along Hamilton’s beach strip, he stated, the same cancer risk is one in 10,000.

“We are the people who really carry that burden,” Bezner said. “We feel the real effects and frankly, we’re worried about them.”

A study led by researcher Denis Corr, chair of Clean Air Hamilton, showed there are indeed significant disparities in health effects at the neighbourhood level.

Corr, formerly with Ontario’s environment ministry, took a mobile air monitoring station to a number of neighbourhoods around the city to collect data.

Overall, Corr found that across the entire city, Hamilton residents had a 4 per cent increased risk of premature death for all air pollutants combined.

But at the neighbourhood level, parts of the city had nearly double the risk of premature death compared to Hamilton’s overall rate.

The neighbourhood around the Eva Rothwell Centre on Wentworth Street North, the area around Jones Road and Arvin Avenue in Stoney Creek, and the Nebo Road area all had increased premature death risks near 8 per cent.

Corr noted there are about 185 premature deaths caused by air pollution in Hamilton annually.

“Of those 185 people who are dying of air pollution in Hamilton, it really looks like it’s particulate matter and nitrogen oxides that are killing them,” Corr said.

What isn’t known, he added, is the proportion of those deaths that are being caused by cancer versus respiratory-related ailments, such as asthma.

The study also found that wind direction can have a significant effect on health impacts and the risk of premature death.

For much of the lower central city, risks are notably higher when the wind blows from the northeast because of Hamilton’s unique geography. With the escarpment acting like a catcher’s mitt, pollutants can become trapped over the lower city.

Several of the speakers noted that no one from the environment ministry attended the summit despite being invited to participate.